Armor has been used throughout history as protective clothing or outer layer intended to prevent harm from projectiles. Today's advanced armor is a layered composite material. In general, modern composite armor includes three layers: (1) an outer region also known as a strike face that is intended to blunt and disrupt the impact of an incoming projectile and to distribute the resulting force, (2) a middle or core region designed to absorb energy and attenuate pressure waves, and (3) an inner region known as a spall liner to minimize and/or prevent complete penetration of the projectile or blast by-products.